JP2866996B2 - Organic polymer solution - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a novel organic polymer solution, and more particularly, to an oxidizing agent having no oxidizing power at ordinary temperature but having an oxidizing power at a temperature of 60.degree. And / or a high-temperature active oxidizing agent) and / or an oxidation catalyst, for example, by casting and drying by heating to immediately obtain a film made of conductive polyaniline. It relates to an organic polymer solution.

[0002]

2. Description of the Related Art A method for producing a conductive organic polymer containing an electrolyte ion as a dopant and having a conductivity of 10 ^-6 S / cm or more by chemically oxidizing and polymerizing aniline with a chemical oxidizing agent is already known. Further, in the production of a conductive organic polymer by such chemical oxidative polymerization, an oxidizing agent having a standard electrode potential defined as an electromotive force in a reduction half-cell reaction based on a standard hydrogen electrode of 0.6 V or more is used. It has already been described in JP-A-61-258831 that it can be used particularly preferably.

[0003] However, since conductive organic polymers are generally insoluble and infusible, they cannot be formed into films by the casting method, which poses a major obstacle in developing applications of conductive organic polymers. I'm sorry. JP-A-60-2
35831 and J. Polymer Sci., Polymer Chem.
As described in Ed., 26 , 1531 (1988), a conductive organic polymer film can be formed on an electrode by electrolytic oxidative polymerization of aniline. It is difficult to obtain a large-area film because it is limited to
High manufacturing costs. Moreover, this film has low strength and is insoluble and infusible.

[0004] Therefore, conventionally, a method of producing an intermediate soluble in an organic solvent, film-forming the solution by a casting method, and then converting the intermediate into a conductive polymer by physical or chemical means. Have been proposed. However, according to this method, a treatment at a high temperature is required, or the conversion of the intermediate to the conductive polymer does not always proceed as theoretically. However, it is not practical as a method for producing a conductive organic polymer film.

In the field of polypyrrole or polythiophene, polymers soluble in organic solvents are known. That is,
Electrooxidative polymerization of thiophene having a long-chain alkyl group as a substituent or pyrrole having an alkanesulfonic acid group as a substituent gives poly (3-alkylthiophene) soluble in organic solvents and polypyrrolealkanesulfonic acid soluble in water, respectively. be able to. Films of these polymers can be obtained from the solution by a casting method. However, this method uses a special monomer and electrolytically polymerizes the monomer, so that the production cost is extremely high.

On the other hand, in the field of chemical oxidative polymerization of aniline, recently, about 1/4 mole of ammonium peroxodisulfate is used as an oxidizing agent for aniline, and aniline is chemically oxidatively polymerized to form an organic solvent-soluble polymer. It has been reported that polyaniline can be obtained (A.
G. MacDiarmid et al., Synthetic Metals, 21, 21 (198
7); AG MacDiarmid et al., L. Alcacer (ed.), Con
ducting Polymers, 105-120 (D. Reidel Publishing C
o., 1987).

However, this polymer is N-methyl-2-
80% as well as pyrrolidone and dimethyl sulfoxide
Since it is also soluble in acetic acid and 60% formic acid aqueous solution, its molecular weight is low. It is also described that a self-supporting film can be obtained from a solution of a polymer such as N-methyl-2-pyrrolidone or dimethyl sulfoxide. Furthermore, it is described that a conductive polymer film doped with acetic acid can be obtained from an acetic acid solution, and this film is de-doped with ammonia. However, the undoped film has low strength due to the low molecular weight of polyaniline, and is easily broken by bending, so that it cannot be put to practical use.

It is also known that aniline can be oxidized with ammonium peroxodisulfate to obtain polyaniline soluble in tetrahydrofuran (J. T.
ang, Synthetic Metals, 24 , 231 (1988). However, this polymer is also considered to have a low molecular weight from the viewpoint of dissolving in tetrahydrofuran. The present inventors have made intensive studies to obtain a high molecular weight organic polymer soluble in organic solvents by chemical oxidative polymerization of aniline, and as a result, while having a much higher molecular weight than conventionally known polyaniline, A quinone diimine / phenylenediamine type polyaniline that is soluble in various organic solvents in the undoped state has been found.

By using a solution obtained by dissolving polyaniline in an organic solvent, a self-supporting polyaniline film can be obtained, and a polyaniline film can be formed on an appropriate substrate. Further, by immersing these films in a protonic acid having a pKa value of 4.8 or less or a solution thereof and performing doping with the protonic acid, a film made of conductive polyaniline can be obtained.

The present inventors have further conducted intensive studies on quinonediimine / phenylenediamine type polyaniline (hereinafter sometimes referred to as oxidized polyaniline) which is soluble in an organic solvent in the above-mentioned undoped state. The above-mentioned oxidized polyaniline is reduced with a reducing agent to obtain an organic solvent-soluble imino-p-phenylene-type polyaniline (hereinafter sometimes referred to as reduced polyaniline), and then a specific electron acceptor is added thereto. It has been found that by doping, polyaniline which is soluble in an organic solvent even in a doping state can be obtained.

When a solution containing such a doped polyaniline is used, the casting method can be used easily.
A tough, flexible conductive polyaniline film having self-supporting properties can be obtained. Also, by casting or coating on an appropriate substrate, a tough and flexible conductive polyaniline film can be formed on the substrate.

However, the above-described method for obtaining a conductive polyaniline is useful only when an electron-accepting dopant, that is, an oxidizing dopant is used as a dopant. In other words, the above method cannot be applied to a proton acid dopant having no oxidizing power.
Mechanistically, when an oxidizing dopant is allowed to act on reduced polyaniline, electrons are extracted from the lone pair of electrons of nitrogen of polyaniline, and as a result, semiquinone radicals are generated, so that polyaniline has conductivity. Therefore, in the case of a non-oxidizable protonic acid dopant, even when it acts on reduced polyaniline, it merely protonates the polyaniline and does not generate semiquinone radicals, thus, polyaniline has conductivity. I do not have.

[0013]

The present inventors have conducted intensive studies to obtain a conductive polyaniline film from a solution containing a protonic acid as a dopant, and as a result, have found that a solution containing reduced polyaniline and a protonic acid is obtained. By coexisting a high-temperature active oxidizing agent, such a solution maintains a stable solution state at room temperature even when the polyaniline is at a considerably high concentration, and further casts such a solution. It has been found that a conductive polyaniline film can be immediately obtained by heating and drying, and the present invention has been accomplished.

[0014]

The organic polymer solution according to the present invention comprises (a)

[0015]

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An organic polymer having an imino-p-phenylene structural unit represented by the following formula as a main repeating unit and being soluble in an organic solvent: (b) a protic acid or a protic acid derivative having a pKa value of 4.8 or less; And (c) an oxidizing agent having no oxidizing power at normal temperature and having an oxidizing power at a temperature of 60 ° C. or higher is dissolved in an organic solvent.

First, the production of an imino-p-phenylene-type solvent-soluble polyaniline will be described. The above imino
The p-phenylene-type solvent-soluble polyaniline can be obtained by the following method. That is,

[0018]

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(Wherein m and n represent the mole fractions of the quinone diimine structural unit and the phenylenediamine structural unit in the repeating unit, respectively, 0 <m <1, 0 <n <1, m +
n = 1. An organic polymer having a quinone diimine structural unit and a phenylenediamine structural unit represented by formula (I) as main repeating units, is soluble in an organic solvent in an undoped state, and is prepared in N-methyl-2-pyrrolidone at 30 ° C. The measured intrinsic viscosity [η] is 0.40 dl
/ g or more, and among the skeleton vibrations of para-substituted benzene in the laser Raman spectrum obtained by excitation with light having a wavelength of 457.9 nm, the Raman line of the skeleton stretching vibration appearing at a higher wavenumber than 1600 cm ^-1 Strength Ia and 1
Reduction of an organic polymer (ie, quinonediimine / phenylenediamine type solvent soluble polyaniline or oxidized polyaniline) having a ratio Ia / Ib of Raman line intensity Ib of skeleton stretching vibration having a wave number lower than 600 cm ^-1 of 1.0 or more. It can be obtained by reduction with an agent.

Here, the quinone diimine / phenylenediamine type solvent-soluble polyaniline is prepared by heating the aniline in a solvent at a temperature of 5 ° C. or lower in the presence of a protonic acid having an acid dissociation constant pKa of 3.0 or lower, preferably. While maintaining the temperature at 0 ° C. or lower, an aqueous solution of an oxidizing agent having a standard electrode potential of 0.6 V or more, which is defined as an electromotive force in a reduction half-cell reaction based on a standard hydrogen electrode, is oxidized per mole of aniline. 2 moles or more, preferably 2 to 2.5 equivalents, which is defined as one mole of the agent divided by the number of electrons required to reduce one molecule of the oxidizing agent, is gradually added, To produce an oxidized aniline polymer, and then dedoping the polymer with a basic substance.

In the production of the oxidized polyaniline doped with the above protonic acid, the oxidizing agent may be manganese dioxide, ammonium peroxodisulfate,
Hydrogen peroxide, ferric salt, iodate and the like are particularly preferably used. Among them, for example, ammonium peroxodisulfate and hydrogen peroxide usually involve 1 to 1.25 mol per 1 mol of aniline since two electrons per molecule are involved in the oxidation reaction. Range quantities are used.

The protonic acid used in the oxidative polymerization of aniline is not particularly limited as long as it has an acid dissociation constant pKa of 3.0 or less. For example, hydrochloric acid, sulfuric acid, nitric acid, perchloric acid, Hydrofluoric acid, hydrofluoric acid,
Hydrofluoric acid, inorganic acids such as hydroiodic acid, benzenesulfonic acid, aromatic sulfonic acids such as p-toluenesulfonic acid, methanesulfonic acid, alkanesulfonic acids such as ethanesulfonic acid, phenols such as picric acid, Examples thereof include aromatic carboxylic acids such as m-nitrobenzoic acid, and aliphatic carboxylic acids such as dichloroacetic acid and malonic acid. Also, polymeric acids can be used. Examples of such a polymer acid include polystyrene sulfonic acid, polyvinyl sulfonic acid, polyallyl sulfonic acid, and polyvinyl sulfate.

The amount of protonic acid used depends on the type of reaction of the oxidizing agent used. For example, in the case of manganese dioxide, the oxidation reaction is represented by MnO ₂ + 4H ⁺ + 2e ⁻ → Mn ²⁺ + 2H ₂ O.
It is necessary to use a protonic acid capable of supplying a double molar amount of protons. Also, in the case of hydrogen peroxide, since the oxidation reaction is represented by H ₂ O ₂ + 2H ⁺ + 2e ⁻ → 2H ₂ O, a proton acid capable of supplying at least twice the amount of protons of hydrogen peroxide to be used is used. There is a need. On the other hand, in the case of ammonium peroxodisulfate,
Since the oxidation reaction is represented by S ₂ O ₈ ²⁻ + 2e ⁻ → 2SO ₄ ²⁻ , it is not particularly necessary to use a protonic acid. However, in the present invention, even when ammonium peroxodisulfate is used as the oxidizing agent, it is preferable to use an equimolar amount of the protonic acid with the oxidizing agent.

As a solvent in the oxidative polymerization of aniline, aniline, a protonic acid and an oxidizing agent are dissolved, and
Those that are not oxidized by an oxidizing agent are used. Water is most preferably used, however, if necessary, alcohols such as methanol and ethanol, nitriles such as acetonitrile, N-methyl-2-pyrrolidone, polar solvents such as dimethyl sulfoxide, ethers such as tetrahydrofuran, Organic acids such as acetic acid can also be used.
Also, a mixed solvent of these organic solvents and water can be used.

In the production of such an oxidized polyaniline doped with a protonic acid, the temperature of the reaction mixture is always kept at 5 ° C. or lower during the oxidation reaction of aniline, especially during the addition of the oxidizing agent solution to the aniline solution. It is important to keep Therefore, the oxidant solution should be added slowly to the aniline so that the temperature of the reaction mixture does not exceed 5 ° C. When the oxidizing agent is added rapidly, the temperature of the reaction mixture increases due to external cooling to produce a low-molecular-weight polymer, or a solvent-insoluble oxidizing polymer even after dedoping described later. Is generated.

In particular, in the above oxidation reaction, it is preferable to keep the reaction temperature at 0 ° C. or lower. As described above, by undoping the doped oxidized polyaniline obtained by maintaining the reaction temperature at 0 ° C. or lower, N-
A high-molecular-weight quinonediimine / phenylenediamine-type solvent-soluble polyaniline having an intrinsic viscosity [η] (hereinafter the same) measured at 30 ° C. in methyl-2-pyrrolidone of at least 1.0 dl / g, that is, an oxidized polyaniline is obtained. be able to.

Since the oxidized polyaniline doped with the above-mentioned protonic acid forms a salt with the protonic acid, the oxidized polyaniline is usually used at such a high concentration that a free-standing film can be prepared. Does not dissolve in organic solvents. It is well known that salts of high molecular weight amines are generally poorly soluble in many organic solvents. However, a solvent-soluble oxidized polyaniline can be obtained by dedoping the organic solvent-insoluble oxidized polyaniline.

Further, as described above, the oxidized polyaniline doped with the used protonic acid is dedoped,
Solvent-soluble oxidized polyaniline is used, for example, N 2
By doping in a dilute solution of -methyl-2-pyrrolidone with, for example, an organic acid such as malonic acid, a doped oxidized polyaniline can be obtained while keeping the solvent soluble.

Since the dedoping of the oxidized polyaniline doped with the above protonic acid is a kind of neutralization reaction, it is not particularly limited as long as it is a basic substance capable of neutralizing the protonic acid as a dopant. Is not something,
Preferably, metal hydroxides such as aqueous ammonia, sodium hydroxide, potassium hydroxide, lithium hydroxide, magnesium hydroxide, and calcium hydroxide are used. In the dedoping, a basic substance may be directly added to the reaction mixture after the oxidative polymerization of aniline, or the basic substance may be allowed to act once the obtained oxidized polyaniline is once isolated.

The doped oxidized polyaniline obtained by the oxidative polymerization of aniline is usually 10%.
^It has a conductivity of ^-6 S / cm or more and exhibits a blackish green color, but after undoping, it is a purple or purple-purple copper color. This discoloration is due to the change of the amine nitrogen in the salt structure of the oxidized polyaniline into a free amine. The conductivity is usually 1
It is on the order of 0 ^-10 S / cm.

The undoped quinone diimine phenylenediamine type, ie, oxidized solvent-soluble polyaniline thus obtained has a high molecular weight and is soluble in various organic solvents. Such organic solvents include N
-Methyl-2-pyrrolidone, N, N-dimethylacetamide, N, N-dimethylformamide, dimethylsulfoxide, 1,3-dimethyl-2-imidazolidinone, sulfolane and the like. The solubility depends on the average molecular weight of the polymer and the solvent, but 0.5 to 100% of the polymer is dissolved, and a solution of 1 to 30% by weight can be obtained.

In particular, the oxidized solvent-soluble polyaniline exhibits high solubility in N-methyl-2-pyrrolidone,
Usually, 20 to 100% of the polymer dissolves to give a 3 to 30% by weight solution. However, it does not dissolve in tetrahydrofuran, 80% acetic acid aqueous solution, 60% formic acid aqueous solution, acetonitrile and the like. Accordingly, the oxidized solvent-soluble polyaniline can be dissolved in an organic solvent and formed into a film by a casting method. For example, by casting an oxidized solvent-soluble polyaniline solution on a glass plate and then selecting the conditions for heating and drying the solvent, a self-supporting oxidized polyaniline film that is uniform, tough, and excellent in flexibility can be obtained. Can be obtained.

In this film preparation, in order to obtain a film which is tough and excellent in flexibility, the intrinsic viscosity [η] is 0.4.
It is desirable to use 0 or more of the above-mentioned oxidized solvent-soluble polyaniline. Furthermore, films obtained by casting oxidized solvent-soluble polyaniline have different properties depending on the drying conditions of the solvent. Usually, N- of soluble polyaniline having an intrinsic viscosity [η] of 0.40 or more
When the methyl-2-pyrrolidone solution is cast on a glass plate and the solvent is dried, the drying temperature is 100 ° C.
When the following conditions are satisfied, the resulting film is still not sufficiently strong and is partially soluble in N-methyl-2-pyrrolidone. However, when the drying temperature is 130 ° C. or higher, the obtained film has excellent flexibility, is very tough, and does not crack even when bent. The film thus obtained does not dissolve in N-methyl-2-pyrrolidone and further does not dissolve in concentrated sulfuric acid. As described above, the solvent insolubilization of the polymer by drying the solvent at a high temperature after the casting is considered to be due to crosslinking of the polymer molecule due to the coupling of radicals existing in the polymer or generated upon heating. Can be

Quinone diimine phenylenediamine type,
That is, the oxidized solvent-soluble polyaniline is, as described above, from elemental analysis, infrared absorption spectrum, ESR spectrum, laser Raman spectrum, thermogravimetric analysis, solubility in a solvent, and visible to near infrared absorption spectrum.

[0035]

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(Wherein, m and n represent the molar fractions of the quinone diimine structural unit and the phenylenediamine structural unit in the repeating unit, respectively; 0 <m <1, 0 <n <1, m +
n = 1. ) Is a polymer having a quinone diimine structural unit and a phenylenediamine structural unit as main repeating units.

A film obtained by insolubilizing a solvent using this quinone diimine / phenylenediamine type solvent-soluble polyaniline by the casting method also shows substantially the same infrared absorption spectrum as that of the solvent-soluble polymer. From an infrared absorption spectrum, an ESR spectrum, a laser Raman spectrum, a thermogravimetric analysis, a solubility in a solvent, a visible to near-infrared absorption spectrum, and the like, it is considered that the polymer has substantially the same repeating unit although it has a crosslinked structure.

Here, the characteristics of the quinonediimine / phenylenediamine-type solvent-soluble polyaniline obtained from the laser Raman spectrum will be described in comparison with conventionally known so-called polyaniline. In general,
Vibration spectroscopy is a means for obtaining information on vibrations between atoms constituting a substance, and includes infrared spectroscopy and Raman spectroscopy. Infrared spectroscopy is active in vibration modes that result in dipole moment changes, and Raman spectroscopy is active in vibrations that cause polarizability changes. Therefore, both
In a complementary relationship, generally, a vibration mode that appears strongly in infrared spectroscopy is weak in Raman spectroscopy, whereas a vibration mode that appears strongly in Raman spectroscopy is weak in infrared spectroscopy.

An infrared absorption spectrum is obtained by detecting the energy absorption between vibrational levels, and a Raman spectrum is obtained after the molecules are excited by light irradiation, to a higher vibrational level in the ground state. It is obtained by detecting the scattered light (Raman scattering) generated when falling. At this time, the vibration energy level can be known from the energy difference of the scattered light with respect to the irradiation light.

Usually, a Raman spectrum is obtained by excitation with visible light from an argon laser or the like. Here, when the sample has an absorption band in the visible region, it is known that a very strong Raman ray can be obtained if the irradiation laser light and the absorption band wavelength match. This phenomenon is called the resonance Raman effect, and according to this, a Raman line as strong as 10 ⁴ to 10 ⁵ times that of a normal Raman line can be obtained. According to the resonance Raman effect, information on the chemical structure excited by the wavelength of the irradiated laser light can be obtained with more enhanced information. Therefore, the chemical structure of the sample can be analyzed more accurately by measuring the Raman spectrum while changing the wavelength of the laser light to be irradiated. Such a feature is a feature of Raman spectroscopy that does not exist in infrared spectroscopy.

FIG. 1 shows that in N-methyl-2-pyrrolidone
A sample of a undoped quinonediimine / phenylenediamine-type solvent-soluble polyaniline powder having an intrinsic viscosity [η] of 1.2 dl / g measured at 30 ° C. was formed into a disk-shaped sample and irradiated with an excitation wavelength of 457.9 nm. It is the obtained laser Raman spectrum. The assignment of the Raman line is as follows. 1622 and 1591 cm ^-1 are the skeleton stretching vibration of para-substituted benzene, 1489 and 1479 cm -1.
^-1, stretching vibration of C = C and C = N quinonediimine structure, 1220 cm ^-1 mixed C-N stretching vibration and C-C stretching vibration, 1185 and 1165 cm ^-1-plane bending of the C-H Vibration.

FIG. 2 shows Y. Furukawa et al., Synth. Me
t, 16 , 189 (1986) is a laser Raman spectrum obtained by irradiating undoped polyaniline at an excitation wavelength of 457.9 nm. This polyaniline is obtained by electrolytic oxidation polymerization of aniline on a platinum electrode. As shown in FIG. 1, in the quinone diimine / phenylenediamine type solvent-soluble polyaniline, 1600 cm ⁻¹ of the skeletal vibration of para-substituted benzene was used.
The ratio Ia / Ib of the Raman line intensity Ia of the skeleton stretching vibration appearing at a higher wavenumber than the Raman line intensity Ib appearing at a wavenumber lower than 1600 cm ^-1 is 1.0 or more. On the other hand, in the conventionally known polyaniline including the polyaniline shown in FIG. 2, the ratio Ia / Ib is smaller than 1.0, including those obtained by chemical oxidative polymerization.

The Raman lines at 1622 cm ^-1 and 1591 cm ^-1 are both based on the skeleton stretching vibration of para-substituted benzene. In the polyaniline in a reduced state, a Raman line is generated only at 1621 cm ⁻¹ because it does not have a quinone diimine structure, but in the undoped polyaniline having a quinone diimine structure, as described above,
Raman lines appear at ^-1 and 1591 cm ^-1 . These Raman lines exhibit excitation wavelength dependence as shown in FIG.

The excitation wavelength is 488.0 nm to 476.5 nm.
As a result, Ia / Ib changes as the wavelength is changed to 457.9 nm on the short wavelength side. That is, at 488.0 nm, Ia / Ib is smaller than 1.0, but at 457.9 nm,
1.0 or more, compared to 488.0 nm.
The Ia / Ib intensity is reversed. This reversal phenomenon will be explained as follows.

FIG. 4 shows an electronic spectrum of a quinone diimine / phenylenediamine type solvent-soluble polyaniline.
Since the peak at 647 nm disappears by reducing the quinone diimine / phenylenediamine type solvent-soluble polyaniline, it is considered to be derived from the quinone diimine structure. The peak at 334 nm is considered to be derived from the π-π ^* transition of para-substituted benzene because the intensity of the peak at 334 nm is increased by reducing polyaniline. FIG. 4 shows the Raman excitation wavelength described above. Here, regarding the band of the para-substituted benzene skeleton stretching vibration, the excitation wavelength was 488.0 n.
When the wavelength is changed from m to 457.9 nm on the short wavelength side, 15
Compared with the band of 91cm ^-1, the resonance condition of the resonance Raman effect of the band of 1622cm ^-1 is more advantageous, it believed to changes in relative intensities as described above occurs.

Next, in the spectra shown in FIGS. 1 and 2, the relative intensities of the Raman lines at 1591 cm ^-1 and 1622 cm ^-1 are different despite the same excitation wavelength (457.9 nm). It will be explained as follows. That is,
N, N'- as model compound of phenylenediamine structure
Diphenyl-p-phenylenediamine has a Raman line only at 1617 cm ⁻¹ , and N, N′-diphenyl-p-benzoquinone diimine as a model compound having a quinone diimine structure has Raman lines at 1568 cm ⁻¹ and 1621 cm ^−1. Therefore, as shown in the following (a), the quinone diimine structure and the non-conjugated para-substituted benzene ring have a Raman line of 1622 cm ^-1 whose intensity is increased by excitation of short wavelength light, and the following (b)
As shown in the above, the para-substituted benzene ring conjugated with the quinone diimine structure is assumed to have Raman lines at 1591 cm ^-1 and 1622 cm ^-1 .

[0047]

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From the results of the elemental analysis, it is considered that the number of quinone diimines and the number of phenylenediamines are almost equal in the quinone diimine / phenylenediamine type solvent-soluble polyaniline. From the connection mode between the structure and the phenylenediamine structure, as shown in (c), an alternating copolymer chain of a quinonediimine structure and a phenylenediamine structure,
As shown in (d), it is classified into two types, a block copolymer-like chain having a quinone diimine structure and a phenylenediamine structure. In the figure, a para-substituted benzene ring indicated by an arrow indicates a benzene ring that is not conjugated to quinone diimine. In the above-mentioned alternating copolymeric chain, for example, two per octamer chain unit, In a united chain, for example, three per octamer chain unit. When the length of the chain unit is long, the difference between the numbers of the quinone diimine and the non-conjugated benzene ring in both cases is further increased. This difference is 1
It can be said that the difference between the relative intensities of the Raman lines at 591 cm ^-1 and 1622 cm ^-1 appears.

[0049]

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Since the quinone diimine / phenylenediamine type solvent-soluble polyaniline has an Ia / Ib ratio of at least 1.0 in the laser Raman spectrum, it contains a large amount of a non-conjugated benzene ring with the quinone diimine structure. It is thought to have the above block copolymer chain. The organic solvent solubility of the quinone diimine / phenylenediamine type solvent soluble polyaniline is reasonably explained by having such a block copolymeric chain. Generally, it is known that an imine nitrogen (-N =) in a quinone diimine structure forms a hydrogen bond with a nearby secondary amino group hydrogen (-NH-) (Macromolecules, 21 , 1297 (1988)). The hydrogen bonds between the secondary amino groups are not strong.

Therefore, when the polyaniline has the above-mentioned alternating copolymer chain, a network having a strong hydrogen bond as shown in (f) is formed. The insolubility of the conventionally known polyaniline in many organic solvents even in the undoped state is considered to be due to the formation of such a network having strong hydrogen bonds. In contrast, when the polymer chain is the block copolymer-like chain such as the solvent-soluble polyaniline in the undoped state according to the present invention, since the block chains usually have different lengths, (e) As seen in (2), even when the phenylenediamine structure portion and the quinonediimine structure portion are adjacent to each other, many hydrogen bonds cannot be formed, and the solvent penetrates between the polymer chains and forms a hydrogen bond with the solvent. To be dissolved in the organic solvent. If the block chains had exactly the same length in all parts, they would form a network of hydrogen bonds as described above, but the probability of having such a structure is extremely small and is usually ignored. I can do it.

[0052]

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[0053]

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Further, such an inter-chain interaction is explained also from the C-H in-plane bending vibration of the laser Raman spectrum. The Raman line at 1162 cm ^-1 attributed to the CH in-plane bending vibration of the undoped quinone diimine / phenylenediamine type solvent-soluble polyaniline shown in FIG. 1 indicates that the polyaniline is reduced and all imine nitrogens When converted to a secondary amino nitrogen, there is a high wave number shift to 1181 cm ^-1 .

As described above, the quinone diimine / phenylenediamine type solvent-soluble polyaniline in the undoped state has two Raman lines at 1165 cm and 1185 cm ^-1 which are attributed to CH in-plane bending vibration. This 1185 cm ^-1 Raman line is not found in the conventionally known undoped polyaniline,
11 belonging to CH in-plane bending vibration in reduced state
It shows a value close to 81 cm ^-1 .

From these points, it is considered that the quinone diimine / phenylenediamine type solvent-soluble polyaniline has a block copolymer chain in the undoped state and has an atmosphere of a reduced structure. This suggests that the polymer has high solubility in organic solvents despite its high molecular weight. As described above, the quinone diimine / phenylenediamine type solvent-soluble polyaniline disclosed herein is a polymer having a structural chain different from conventionally known polyaniline.

As described above, the oxidized polymer doped with the protonic acid obtained by the oxidative polymerization of aniline has quinone diimine structural units and phenylenediamine structural units in a block copolymer chain as repeating units. Therefore, in the state doped with a protonic acid, it is described as having conductivity only by an acid-base reaction without an oxidation-reduction reaction.
This conductive mechanism is based on AGMacDiarmid et al. (AG MacDiarmid et al., J. Chem. Soc., Chem. Com.
mun., 1987, 1784), by doping with a protonic acid, as shown below, the quinone diimine structure is protonated, which has a semiquinone cation radical structure and has conductivity. Such a state is called a polaron state.

[0058]

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As described above, the quinone diimine / phenylenediamine type solvent-soluble polyaniline can be dissolved in an organic solvent to form a self-supporting film by a casting method. The composite film can also be obtained by film formation by the method. Such a film can be easily made conductive by doping it with a protonic acid. Here, as the protonic acid, those described above can be used.

Before doping, the film has a reflected light color of copper and a transmitted light color of blue, but after doping with a protonic acid, the reflected light has a blue color and the transmitted light has a green color. Further, after doping, a near infrared region (1000
２０００2000 nm) changes significantly. That is, before doping, near-infrared light is almost reflected, but after doping, near-infrared light is almost absorbed.

The conductivity of the conductive film obtained by doping depends on the pKa value of the protonic acid used.
The pKa value of 4.8 for the doping of oxidized aniline polymers.
The following proton acids are effective, and when a pKa value of 1 to 4.8 is used, the smaller the pKa value, that is, the stronger the acidity, the higher the conductivity of the obtained film. However, when the pKa value is smaller than 1, the electric conductivity of the obtained film no longer changes and is almost constant. However, of course, a protonic acid having a pKa value of 1 or less may be used, if necessary.

As described above, the conductivity of the conductive film obtained by doping the quinone diimine / phenylenediamine type solvent-soluble polyaniline with a protonic acid is usually 10 ⁻⁶ S / cm or more, and in many cases, 10 ⁻ S / cm. ⁴ S /
cm or more. This conductive film is also tough,
It does not break easily when bent. However, this conductive film is doped with a protonic acid, similarly to the conductive polymer prepared in the presence of a protonic acid. It does not dissolve in the above-mentioned organic solvent due to the cross-linking of the radical generated in the heat evaporation step by coupling.

However, according to the present invention, by reducing the above-mentioned quinonediimine / phenylenediamine-type solvent-soluble polyaniline with a reducing agent, the imino-p-phenylene-type solvent soluble in various organic solvents can be further reduced. Polyaniline can be obtained, and further, if a solution containing such a solvent-soluble imino-p-phenylene-type polyaniline, a protonic acid and the above-mentioned thiuram compound is prepared, such a solution can be cast and dried only. To provide a conductive polyaniline film.

Examples of the reducing agent include phenylhydrazine, hydrazine, hydrazine hydrate, hydrazine sulfate,
Hydrazine compounds such as hydrazine hydrochloride and reductive metal hydride compounds such as lithium aluminum hydride and lithium borohydride are preferably used. Hydrazine hydrate or phenylhydrazine is particularly preferably used as the reducing agent since no residue is produced after the reduction reaction.

The method for reducing the quinone diimine / phenylenediamine type solvent-soluble polyaniline with the above reducing agent may be a conventional reduction reaction method, and is not particularly limited. For example, quinone diimine / phenylenediamine type solvent-soluble polyaniline is converted to N-methyl-2.
-Dissolving in an organic solvent such as pyrrolidone, adding the above reducing agent to this solution, dissolving the reducing agent in an organic solvent such as N-methyl-2-pyrrolidone, dimethylformamide, dimethylacetamide, and adding quinonediimine. A method of adding phenylenediamine-type solvent-soluble polyaniline or a method of dispersing quinonediimine / phenylenediamine-type solvent-soluble polyaniline in a non-solvent and performing a reduction reaction in a heterogeneous system can be used.

According to the present invention, the reduction reaction is carried out by adding quinone diimine / phenylenediamine type solvent-soluble polyaniline to the polyaniline in an amount of usually 0.1 to 15% by weight, preferably 0.5 to 10% by weight.
It is performed in a solution containing. The reducing agent may be usually used in an amount equivalent to the amount of quinone diimine in the quinone diimine / phenylenediamine type solvent-soluble polyaniline, but may be used in an amount exceeding the equivalent in order to accelerate the progress of the reaction.

However, when an excess of the reducing agent is used as described above, the resulting imino-p-phenylene type solvent-soluble polyaniline, when stored in a solution state as it is, for a long period of time, is not polymerized. In some cases, the molecular weight may be reduced due to cleavage of the molecular chain. Therefore, when an excess reducing agent is used, it is preferable that the obtained imino-p-phenylene-type solvent-soluble polyaniline is separated and purified by a reprecipitation method, and then doped.

The imino-p-phenylene type solvent-soluble polyaniline obtained in this manner is quinone diimine.
It has better solubility in various organic solvents than phenylenediamine-type solvent-soluble polyaniline. For example, imino-p-phenylene-type solvent-soluble polyaniline is well dissolved in dimethylformamide, dimethylacetamide, dimethylsulfoxide and the like at a high concentration of several weight% or more.

As described above, the imino-p-phenylene-type solvent-soluble polyaniline is more soluble in the organic solvent because, as described in the structural analysis of the quinonediimine-phenylenediamine-type solvent-soluble polyaniline by Raman spectrum, the polymer chain is dissolved. It is considered that the quinone diimine structure in the polymer disappeared by reduction, so that hydrogen bonds between polymer chains were greatly weakened.

In this reduction reaction, the molecular chain is generally not substantially cleaved at the time of the reaction, and the resulting imino-p-phenylene-type solvent-soluble polyaniline is obtained from the initial quinonediimine / phenylenediamine-type solvent-soluble polyaniline. It is confirmed from the measurement of the intrinsic viscosity [η] of the resulting imino-p-phenylene-type solvent-soluble polyaniline that the polymer has the high molecular weight. The resulting imino-p-phenylene-type solvent-soluble polyaniline usually has an intrinsic viscosity [η] of 0.40 dl / g or more measured in N-methyl-2-pyrrolidone at 30 ° C.

The organic polymer solution according to the present invention is obtained by dissolving a protonic acid having a pKa value of 4.8 or less and the above-mentioned high temperature active oxidizing agent in a solution of the imino-p-phenylene type solvent-soluble polyaniline. Can be obtained. The protonic acid used in the present invention has an acid dissociation constant pK
a Inorganic acids and organic acids having a value of 4.8 or less. Examples of the inorganic acid include hydrofluoric acid, phosphoric acid, perchloric acid, and the like. When the protonic acid is a mineral acid such as sulfuric acid, hydrochloric acid, or nitric acid, the polymer doped with these is difficult to dissolve in an organic solvent.

The above-mentioned organic acids having an acid dissociation constant pKa of 4.8 or less include mono- or polybasic acids such as aliphatic, aromatic, araliphatic, alicyclic and the like. May have a hydroxyl group, a halogen, a nitro group, a cyano group, an amino group and the like. Therefore, as a specific example of such an organic acid,
For example, acetic acid, n-butyric acid, pentadecafluorooctanoic acid, pentafluoroacetic acid, trifluoroacetic acid, trichloroacetic acid, dichloroacetic acid, monofluoroacetic acid, monobromoacetic acid, monochloroacetic acid, cyanoacetic acid, acetylacetic acid, nitroacetic acid, triphenylacetic acid, Formic acid, oxalic acid, benzoic acid, m-bromobenzoic acid, p-chlorobenzoic acid, m-chlorobenzoic acid, p-chlorobenzoic acid, o-nitrobenzoic acid, 2,4-dinitrobenzoic acid, 3,5- Dinitrobenzoic acid, picric acid, o-chlorobenzoic acid, p-nitrobenzoic acid, m-nitrobenzoic acid, trimethylbenzoic acid, p-
Cyanobenzoic acid, m-cyanobenzoic acid, thymol blue, salicylic acid, 5-aminosalicylic acid, o-methoxybenzoic acid, 1,6-dinitro-4-chlorophenol, 2,
6-dinitrophenol, 2,4-dinitrophenol,
p-oxybenzoic acid, bromophenol blue, mandelic acid, phthalic acid, isophthalic acid, maleic acid, fumaric acid, malonic acid, tartaric acid, citric acid, lactic acid, succinic acid, α
-Alanine, β-alanine, glycine, glycolic acid,
Thioglycolic acid, ethylenediamine-N, N'-diacetic acid,
Ethylenediamine-N, N, N ', N'-tetraacetic acid and the like can be mentioned.

The organic acid may have a sulfonic acid or a sulfuric acid group. Such organic acids include, for example, aminonaphtholsulfonic acid, metanilic acid, sulfanilic acid, allylsulfonic acid, lauryl sulfate, xylenesulfonic acid, chlorobenzenesulfonic acid,
1-propanesulfonic acid, 1-butanesulfonic acid, 1-
Hexanesulfonic acid, 1-heptanesulfonic acid, 1-octanesulfonic acid, 1-nonanesulfonic acid, 1-decanesulfonic acid, 1-dodecanesulfonic acid, benzenesulfonic acid, styrenesulfonic acid, p-toluenesulfonic acid,
Naphthalenesulfonic acid and the like can be mentioned.

In the present invention, a polyfunctional organic sulfonic acid having two or more sulfonic acid groups in a molecule can also be preferably used as a protonic acid. Such polyfunctional organic sulfonic acids include, for example, ethane disulfonic acid, propane disulfonic acid, butane disulfonic acid, pentane disulfonic acid, hexane disulfonic acid, heptane disulfonic acid, octane disulfonic acid, nonane disulfonic acid, decane disulfonic acid, benzene disulfonic acid , Naphthalene disulfonic acid, naphthalene trisulfonic acid, naphthalene tetrasulfonic acid, anthracene disulfonic acid,
Anthraquinone disulfonic acid, phenanthylene disulfonic acid, fluorenone disulfonic acid, carbazole disulfonic acid, diphenylmethane disulfonic acid, biphenyl disulfonic acid, terphenyl disulfonic acid, terphenyl trisulfonic acid, naphthalene sulfonic acid-formalin condensate, phenanthrene sulfonic acid Formalin condensate,
Examples include anthracenesulfonic acid-formalin condensate, fluorenesulfonic acid-formalin condensate, and carbazolesulfonic acid-formalin condensate. The position of the sulfonic acid group in the aromatic ring is arbitrary.

Further, the organic acid may be a polymer acid. Examples of such a polymer acid include polyvinyl sulfonic acid, polyvinyl sulfuric acid, polystyrene sulfonic acid, sulfonated styrene-butadiene copolymer, polyallyl sulfonic acid, polymethacryl sulfonic acid, and poly-2.
-Acrylamide-2-methylpropanesulfonic acid, polyhalogenated acrylic acid, and the like.

A fluorine-containing polymer known as Naphion (registered trademark of DuPont, USA) is also suitably used as the polymer acid. In general, the solubility of a conductive organic polymer in a doped state differs depending on the molecular weight of a polymer acid. Generally, lower molecular weight polymeric acids provide more soluble, doped organic conductive polymers.

Further, ammonium salts and amine salts of these protonic acids can also be used as dopants.
Examples of such a dopant include an ammonium salt of p-toluenesulfonic acid, a triethylamine salt of p-toluenesulfonic acid, and a triethylamine salt of ethanedisulfonic acid. When the dopant is used in excess with respect to polyaniline, the strength of the conductive polyaniline film obtained by casting and drying the obtained solution may be low. Therefore, when preparing the polyaniline solution, the amount of the protonic acid added to the polyaniline is preferably equivalent to or less than the amino group of the main chain of polyaniline, more preferably 0.75 equivalent or less, and particularly preferably. Is less than 0.5 equivalent.

The oxidizing agent used in the present invention will be described. The oxidizing agent used in the present invention is a high-temperature activating oxidizing agent having an oxidizing power only during heating and drying. Preferred examples of such an oxidizing agent include, for example, a thiuram-based compound, a sulfenamide-based compound, and an oxime-based compound. The oxidizing agent used in the present invention promotes vulcanization of the rubber by a vulcanizing agent, shortens the vulcanizing time, lowers the vulcanizing temperature, reduces the amount of sulfur, etc. It is a type of vulcanization accelerator well known as a rubber chemical for improving properties.

In the present invention, the thiuram-based compound used as the above-mentioned high-temperature active type oxidizing agent has the above formula

[0080]

Embedded image

(Wherein Ra, Rb, Rc and Rd each independently represent an alkyl group, and x represents an integer of 1 to 6). Examples of such thiuram compounds include, for example, tetramethylthiuram monosulfide, tetraethylthiuram monosulfide, tetrapropylthiuram monosulfide, tetrabutylthiuram monosulfide,
Monosulfides such as dipentamethylenethiuram monosulfide, tetramethylthiuram disulphide, tetraethylthiuram disulphide, tetrapropylthiuram disulphide, tetrabutylthiuram disulphide, N,
Disulfides such as N'-dimethyl-N, N'-diphenylthiuram disulphide, dipentamethylenethiuram disulphide, dicyclopentamethylenethiuram disulphide, and tetrasulfides such as dipentamethylenethiuram tetrasulfide And hexasulfides such as dipentamethylenethiuram hexasulfide.

In the present invention, the sulfenamide compound used as the high-temperature active oxidizing agent is represented by the above formula

[0083]

Embedded image

(Wherein, Re and Rf each independently represent a hydrogen atom, an alkyl group or an oxyalkylene group). Examples of such sulfenamide-based compounds include, for example, cyclohexylbenzothiazylsulfenamide, dicyclohexylbenzothiazylsulfenamide, oxydiethylenebenzothiazylsulfenamide, butylbenzothiazylsulfenamide, dipropylbenzothiazylsulfur Fuenamide and the like can be mentioned.

In the present invention, the oxime compound used as the high-temperature active oxidizing agent is represented by the formula

[0086]

Embedded image

(Wherein, Rg and Rh each independently represent a hydroxyl group or a benzoyl group). Examples of such oxime compounds include p-quinone dioxime and p, p'-dibenzoylquinone dioxime. However, the high-temperature activating oxidizing agent used in the present invention is not limited to the above-mentioned oxidizing agents. , Anything.

Further, in the present invention, together with an oxidizing agent,
An oxidation catalyst that promotes oxidation by the oxidizing agent may be mixed with the solution. Such an oxidation catalyst accelerates the rate of oxidation by the oxidizing agent when the oxidizing agent is dried by heating, and allows the polyaniline film to exhibit electrical conductivity at an early stage, thereby obtaining high electrical conductivity. Such an oxidation catalyst is, for example, preferably at least one selected from the group consisting of cobalt, iron or manganese stearate, naphthenate and acetylacetonate, particularly cobalt stearate, cobalt naphthenate , Cobalt (II) acetylacetonate and the like are preferably used.

The oxidation reaction of the high-temperature oxidizing agent in the present invention will be described. For example, in the case of a thiuram compound, such an oxidizing agent generates a radical species by heating in the drying process of the reduced polyaniline solution according to the present invention,
It is presumed that these radicals extract hydrogen radicals from the protonated reduced polyaniline present in the system, and thus generate semiquinone radicals, leading to polyaniline having conductivity.

That is, this mechanism

[0091]

Embedded image

As shown in FIG. Such thiuram compounds generate radical species only by heating unless ultraviolet irradiation is performed. An oxidizing agent having reactivity at room temperature, like a normal oxidizing agent, easily oxidizes this polyaniline when coexisting with polyaniline in a solution,
Here, since the doped polyaniline has low solubility, when the polyaniline concentration is several weight% or more,
Since precipitation easily occurs or the solution solidifies, the solution state cannot be stably maintained. On the other hand, since the thiuram compound generates a radical species only by heating, when the thiuram compound is in a solution in the presence of reduced polyaniline and a protonic acid, the solution is stable unless heated.

In the present invention, the high temperature active oxidizing agent is
It is used in an amount of 0.01 to 1 molecule, preferably 0.1 to 0.6 molecule per 4 imino-p-phenylene structural units of the reduced polyaniline. Such a solution according to the invention gives an electrically conductive polyaniline upon casting and heat drying. The heating and drying conditions depend on the thickness of the resulting polyaniline film, but are, for example, 20 to 30 μm.
When a polyaniline film having a thickness of
5 to 1 at a temperature of 200 ° C, preferably 100 to 160 ° C.
Heat drying for 20 minutes, preferably 15 to 60 minutes, is suitable. The resulting conductive polyaniline film usually has a conductivity of about 10 −3 to 10 −1 S / cm. From the ESR spectrum of the obtained conductive polyaniline film, generation of radicals having a spin concentration of 10 19 to 10 20 spin / g is recognized. This radical is considered to be derived from the semiquinone radical generated by the mechanism described above. When a thin film having a thickness of about 0.05 μm is to be obtained, heat drying is usually performed at a temperature of 60 to 150 ° C., preferably 80 to 100 ° C. for 10 seconds to 5 minutes, preferably 10 seconds to 1 minute. .

[0094]

As described above, the imino-p according to the present invention is
-Phenylene-type solvent-soluble polyaniline with a pKa value of 4.8
The solution containing the following protonic acid and the high-temperature active oxidizing agent is a stable solution at room temperature, and
This is cast or coated and dried by heating to immediately give a self-supporting conductive polyaniline film. It is also easy to obtain a conductive film having a large area.

Accordingly, the organic polymer solution according to the present invention comprises
It can be used for a wide range of applications. For example, if a film is formed on an insulating substrate using the solution according to the present invention, since this conductive film is electronically conductive, it is stable on the substrate without being affected by moisture or moisture. High antistatic performance. In the production of a release sheet or an adhesive tape, an antistatic property can be imparted by forming a conductive polyaniline film on a substrate using the solution according to the present invention. Furthermore,
Such a conductive film can also be suitably used as a solid electrolyte in a solid electrolytic capacitor or an electromagnetic wave shielding material in various electronic devices. Furthermore, if the solution according to the present invention is spun by a usual method, a conductive fiber can be obtained immediately.

[0096]

The present invention will be described below with reference to examples together with reference examples, but the present invention is not limited to these examples. Reference Example 1 (Production of doped organic polymer by oxidative polymerization of aniline) Distilled water 6 in a 10-liter separable flask equipped with a stirrer, a thermometer, and a straight pipe adapter.
000 g, 360 ml of 36% hydrochloric acid and 400 g of aniline
(4.295 mol) were charged in this order to dissolve the aniline. Separately, while cooling with ice water, 434 g (4.295 mol) of 97% concentrated sulfuric acid was added to 1493 g of distilled water in a beaker and mixed to prepare an aqueous sulfuric acid solution. This aqueous sulfuric acid solution was added to the separable flask, and the entire flask was cooled to −4 ° C. in a low-temperature constant temperature bath.

Next, 980 g (4.295 mol) of ammonium peroxodisulfate was added to 2293 g of distilled water in a beaker and dissolved to prepare an oxidizing agent aqueous solution. The entire flask was cooled in a low-temperature constant temperature bath, and while maintaining the temperature of the reaction mixture at −3 ° C. or lower, the ammonium peroxodisulfate was added to the acidic aqueous solution of the aniline salt from a straight pipe adapter using a tubing pump while stirring. 1 ml of aqueous solution
/ Min. Initially, the colorless and transparent solution changes from green-blue to black-green as the polymerization proceeds,
Subsequently, a black-green powder precipitated.

[0098] During the powder deposition, an increase in the temperature of the reaction mixture is observed.
In order to obtain a high molecular weight polymer, the temperature in the reaction system is set to 0 ° C.
It is important to keep the temperature below, preferably -3 ° C or less. After powder deposition, the dropping rate of the aqueous solution of ammonium peroxodisulfate may be slightly increased, for example, to about 8 ml / min. However, also in this case, it is necessary to adjust the dropping speed so as to keep the temperature at −3 ° C. or lower while monitoring the temperature of the reaction mixture. After completion of the dropwise addition of the aqueous solution of ammonium peroxodisulfate over a period of 7 hours, stirring was continued for a further 1 hour at a temperature of -3C or lower.

The obtained polymer powder was separated by filtration, washed with water and acetone, and dried in vacuum at room temperature to obtain 430 g of a black-green polymer powder. This was pressed into a disk having a diameter of 13 mm and a thickness of 700 μm, and its electric conductivity was measured by the Van der Pauw method. As a result, it was 14 S / cm. (Production of Quinonediimine / Phenylenediamine Solvent-Soluble Polyaniline by Dedoping Conductive Organic Polymer) Doped Conductive Organic Polymer Powder 350
g was added to 4 liters of 2N aqueous ammonia, and the mixture was stirred at 5,000 rpm for 5 hours with an auto homomixer.
The mixture turned from black green to bluish purple.

The powder was filtered off with a Buchner funnel and washed repeatedly with distilled water while stirring in a beaker until the filtrate became neutral, and then washed with acetone until the filtrate became colorless. did. Thereafter, the powder is vacuum-dried at room temperature for 10 hours to obtain a black-brown undoped polymer powder 2.
80 g were obtained. This polymer was soluble in N-methyl-2-pyrrolidone, and the solubility was 8 g (7.4%) per 100 g of the same solvent. This is used as a solvent for 30
The intrinsic viscosity [η] measured at ° C. was 1.23.

This polymer had a solubility of 1% or less in dimethyl sulfoxide and dimethylformamide.
Tetrahydrofuran, pyridine, 80% acetic acid aqueous solution, 6
It did not substantially dissolve in 0% formic acid aqueous solution and acetonitrile. FIG. 1 shows a laser Raman spectrum obtained by irradiating a sample of the undoped quinone diimine / phenylenediamine type solvent-soluble polyaniline powder in a disk shape at an excitation wavelength of 457.9 nm.

For comparison, see Y. Furukawa et al., Syn.
Th. Met., 16 , 189 (1986) shows a laser Raman spectrum obtained by irradiating the undoped polyaniline at an excitation wavelength of 457.9 nm. This polyaniline is obtained by electrolytic oxidation polymerization of aniline on a platinum electrode. FIG. 3 shows the results of measuring the Raman spectrum in the range of 1400 to 1700 cm ^-1 by changing the wavelength of the laser excitation light. The excitation wavelength was changed from 488.0 nm to 477.9 nm to 457.9 nm.
As the wavelength is changed to the shorter wavelength side, Ia / Ib changes. At 457.9 nm, Ia / Ib is 1.0 or more.
It is shown that the Ia / Ib intensity is reversed as compared with the case of 88.0 nm.

FIG. 4 shows an electronic spectrum. Next, the above-mentioned organic solvent-soluble polyaniline was subjected to GP analysis using a GPC column for N-methyl-2-pyrrolidone.
C measurements were made. As the column, three kinds of columns for N-methyl-2-pyrrolidone were used in combination. The eluent used was a 0.01 mol / liter solution of lithium bromide in N-methyl-2-pyrrolidone. FIG. 5 shows the results of the GPC measurement.

From the results, the quinone diimine / phenylenediamine type solvent-soluble polyaniline had a number average molecular weight of 23,000 and a weight average molecular weight of 160,000 (both in terms of polystyrene). Similarly, the reaction conditions were variously changed, and N-methyl-2-pyrrolidone was used at 30 ° C.
To obtain quinone diimine / phenylenediamine type solvent-soluble polyanilines having different intrinsic viscosities [η] measured in the above. Table 1 shows the intrinsic viscosity [η] and the number-average molecular weight and weight-average molecular weight measured by GPC.

[0105]

[Table 1]

Reference Example 2 (Preparation of self-supporting film using soluble aniphosphorylated polymer) 5 g of the undoped aniphosphorylated polymer powder obtained in Reference Example 1 was added to 95 g of N-methyl-2-pyrrolidone. To give a black-blue solution. When this solution was vacuum-filtered with a G3 glass filter, an extremely small amount of insoluble matter remained on the filter. The filter was washed with acetone, the remaining insolubles were dried, and the weight was measured. Therefore,
98.5% of the polymer was dissolved, and 1.5% of the insoluble matter was dissolved.

The thus obtained quinone diimine.
A solution of a phenylenediamine-type solvent-soluble polyaniline was cast on a glass plate, and then was wrung with a glass rod. Then, N-methyl-2-pyrrolidone was evaporated and evaporated in a circulating hot air dryer. Thereafter, the polymer film was naturally peeled off from the glass plate by immersing the glass plate in cold water, thus obtaining a polymer film having a thickness of 40 μm.

After washing this film with acetone, it was air-dried at room temperature to obtain a film having a copper-colored metallic luster. Films differ in strength and solubility depending on the drying temperature. When the drying temperature is 100 ° C. or lower, the obtained film dissolves in a small amount in N-methyl-2-pyrrolidone and has relatively low strength. However, a film obtained by heating at a temperature of 130 ° C. or more is very tough and does not dissolve in N-methyl-2-pyrrolidone or other organic solvents. Also, it does not dissolve in concentrated sulfuric acid. Thus, when heated at a high temperature, the polymer molecules are expected to crosslink with each other in the process and become insoluble.

The undoped quinone diimine / phenylenediamine type solvent-soluble polyaniline film thus obtained has an electric conductivity of 10 ⁻¹¹ S / cm.
I was on a stand. The film did not break even after being bent 10,000 times, and had a tensile strength of 850 kg / cm ² . Reference Example 3 (Doping of a self-supporting film with a protonic acid) In Reference Example 2, the self-supporting film obtained by heating and drying at 160 ° C. for 2 hours was placed in a 1N aqueous solution of sulfuric acid, perchloric acid and hydrochloric acid at room temperature for 66 hours. After soaking for a time, the film was washed with acetone and air-dried to obtain a conductive film.

Each of the films exhibited a deep blue color, and the electrical conductivity was 9 S / cm, 13 S / cm and 6 S / cm, respectively. The tensile strength of the film doped with perchloric acid was 520 kg / cm ² . Reference Example 4 (Spectrum and structure of quinone diimine / phenylenediamine type polyaniline soluble in both undoped state and insoluble film-formed polyaniline) The soluble polymer powder obtained in Example 1 and the insoluble weight obtained in Reference Example 2 FIGS. 6 and 7 show FT-IR spectra of the combined film by the KBr tablet method, respectively. The spectrum of the insoluble polymer film obtained in Reference Example 2 shows the residual solvent N-methyl-
Although the absorption at 1660 cm ^-1 which is considered to be due to 2-pyrrolidone is slightly observed, since the two spectra are almost the same, the polymer is crosslinked by heating and drying the solvent after casting the solvent-soluble polymer. Thus, although the solvent was insolubilized, no significant change in the chemical structure was observed.

FIG. 8 shows the results of thermogravimetric analysis of the soluble polymer powder and the insoluble polymer film. All have high heat resistance. Considering that the insoluble film does not decompose to a higher temperature and is insoluble in concentrated sulfuric acid, it indicates that the polymer molecules are crosslinked in the insoluble film. FIG. 9 shows an ESR spectrum. The spin concentration of the soluble polymer was 1.2 × 10
¹⁸ spin / g, indicating that the spin concentration increases as the heating temperature is increased, indicating that radicals are generated by heating. It is believed that this radical coupling causes the polymer to crosslink and render the heated film insoluble.

Next, the soluble polymer and the insoluble polymer will be described.
The results of the elemental analysis are shown below. Soluble polymer C, 77.19; H, 4.76; N, 14.86 (96.81 in total)Insoluble polymer C, 78.34; H, 4.99; N, 15.16 (total 98.49) Based on this elemental analysis, the soluble standardized to C12.00
The composition formula of the conductive polymer is C12.00 H8.82 N1.98,
The compositional formula of the hydrophilic polymer is C12.00 H9.11 N1.99. other
Similarly, the quinone diimine structure standardized to C12.00
The structural unit and the phenylenediamine structural unit
It is as described.Quinone diimine structural unit C12 H8 N2Phenylenediamine structural unit C12 H10 N2 Therefore, both soluble and solvent-insoluble
Quinone diimine structural unit and phenylenediamine
A polymer having a min structural unit as the main repeating unit
is there.

Next, reflection of the undoped quinone diimine / phenylenediamine type solvent-soluble polyaniline film obtained in Reference Example 2 and the perchloric acid-doped film obtained in Reference Example 3 in the visible to near infrared region. Each spectrum is shown in FIG. In the undoped state, almost near-infrared light is reflected, but after doping, near-infrared light is absorbed, and it is recognized that there is almost no reflection. This is based on absorption by polarons or bipolarons which provides the conductivity created by proton acid doping.

By doping the undoped film with perchloric acid, the ESR absorption is greatly increased and the spin concentration reaches 3.8 × 10 ²¹ spin / g.
This is derived from the generated polaron, a semiquinone radical. Reference Example 5 The polymer film obtained in Reference Example 2 was immersed in an aqueous solution or an alcohol solution of a protonic acid having various pKa values to examine whether or not doping was possible. Table 2 shows the conductivity of the polymer films obtained by doping with protonic acids having various pKa values. Protonic acids with a pKa value of 4.8 or less are shown to be effective for polymer doping.

[0115]

[Table 2]

Reference Example 6 (Preparation of imino-p-phenylene-type solvent-soluble polyaniline) 90 g of the quinonediimine / phenylenediamine-type solvent-soluble polyaniline obtained in Reference Example 1 was added to 400 ml of ethyl ether, and the mixture was stirred and dispersed. . 26.93 g of phenylhydrazine was added little by little to this, and after a while nitrogen gas began to flourish. After stirring was continued for 2.5 hours as it was, the mixture was suction-filtered with a nutsier, and washed several times with acetone substituted with nitrogen.

The polymer powder thus obtained was vacuum-dried at room temperature for 7 hours to obtain 86.6 g of an imino-p-phenylene-type solvent-soluble polyaniline as an off-white powder. This polymer was stored in a glove box purged with argon. Example 1 15 g of the imino-p-phenylene-type organic solvent-soluble polyaniline obtained in Reference Example 6 was dissolved in 85 g of N-methyl-2-pyrrolidone to prepare 100 g of a 15% by weight solution, and then G-2 glass filter. And filtered. This is referred to as solution A.

Separately, p-toluenesulfonic acid monohydrate 9.
45 g was dissolved in 90.55 g of N-methyl-2-pyrrolidone to prepare 100 g of a 9.45% by weight solution. This is referred to as solution B. Tetramethylthiuram disulphide 0.49
5 g was dissolved in 10 g of this solution B. Next, the solution containing the p-toluenesulfonic acid and the thiuram compound dissolved therein was gradually added to 10 g of the solution A with stirring to obtain a uniform solution without forming a precipitate. This solution was cast on a glass plate and kept at 120 ° C. for 30 minutes.
After drying for 25 minutes, a free-standing polyaniline film having a thickness of 25 μm was obtained. The conductivity of this film is 1.67 S / cm
It was. Comparative Example 1 A polyaniline was obtained in the same manner as in Example 1 except that tetramethylthiuram disulfide was not dissolved in Solution B. The conductivity of this film is 8.
It was 8 × 10 ⁻³ S / cm. Put this film in the air
Was allowed to stand week, the conductivity of the film is 10 ⁰ S / cm
It became a stand. Example 2 In Example 1, tetrabutylthiuram disulphide 0.508 was used instead of tetramethylthiuram disulphide.
A homogeneous polyaniline solution was obtained without precipitation, in the same manner as in Example 1 except that g was used.

Using this solution, a 28 μm-thick self-supporting polyaniline film was obtained in the same manner as in Example 1. The conductivity of this film was 0.12 S / cm. Example 3 In Example 1, dipentamethylenethiuram tetrasulfide was used in place of tetramethylthiuram disulfide.
Using 0.478 g, a homogeneous solution containing p-toluenesulfonic acid, a thiuram compound and polyaniline was obtained in the same manner as in Example 1 without forming a precipitate.

Using this solution, a self-supporting polyaniline film having a thickness of 30 μm was obtained in the same manner as in Example 1. The conductivity of this film was 0.68 S / cm. Example 4 Example 1 was repeated, except that 0.352 g of N-oxydiethylene-2-benzothiazylsulfenamide was used in place of tetramethylthiuram disulfide.
In the same manner as described above, a uniform polyaniline solution was obtained without producing a precipitate.

Using this solution, a 28 μm-thick self-supporting polyaniline film was obtained in the same manner as in Example 1. The conductivity of this film was 0.21 S / cm. Example 5 The procedure of Example 1 was repeated, except that instead of tetramethylthiuram disulfide, 0.329 g of cyclohexylbenzothiazylsulfenamide was used. A polyaniline solution was obtained.

Using this solution, a 28 μm-thick self-supporting polyaniline film was obtained in the same manner as in Example 1. The conductivity of this film was 0.23 S / cm. Example 6 The procedure of Example 1 was repeated, except that 0.171 g of p-quinone dioxime was used in place of tetramethylthiuram disulfide. A solution was obtained.

Using this solution, a 28 μm-thick self-supporting polyaniline film was obtained in the same manner as in Example 1. The conductivity of this film was 2.1 S / cm. Example 7 In Example 1, p, p'-dibenzoylquinone dioxime 1.44 was used in place of tetramethylthiuram disulfide.
A uniform polyaniline solution was obtained without forming a precipitate in the same manner as in Example 1 except that g was used.

Using this solution, a 28 μm-thick self-supporting polyaniline film was obtained in the same manner as in Example 1. The conductivity of this film was 0.96 S / cm. Example 8 The procedure of Example 6 was repeated, except that 0.778 g of cobalt stearate was dissolved before dissolving the p-quinone dioxime.
A homogeneous polyaniline solution was obtained.

Using this solution, a 28 μm-thick self-supporting polyaniline film was obtained in the same manner as in Example 1. The conductivity of this film was 10.9 S / cm. Example 9 A homogeneous polyaniline solution was prepared in the same manner as in Example 1, except that 0.778 g of cobalt stearate was used instead of tetramethylthiuram disulfide. Obtained.

Using this solution, a 28 μm-thick self-supporting polyaniline film was obtained in the same manner as in Example 1. The conductivity of this film was 0.35 S / cm. Example 10 10 g of the imino-p-phenylene-type organic solvent-soluble polyaniline obtained in Reference Example 6 was dissolved in 90 g of N-methyl-2-pyrrolidone to prepare 100 g of a 10% by weight solution. And filtered. This is designated as solution C.

Separately, 5.97 g of 1,5-naphthalenedisulfonic acid tetrahydrate was dissolved in 94 g of N-methyl-2-pyrrolidone to prepare 100 g of a 5.97% by weight solution. This is referred to as solution D. 0.198 g of tetramethylthiuram disulphide was dissolved in 10 g of this solution D. Then
The solution containing the 1,5-naphthalenedisulfonic acid and the thiuram compound dissolved therein was gradually added to 10 g of the solution C under stirring to obtain a uniform solution without forming a precipitate. This solution was cast on a glass plate,
The resultant was dried by heating at 30 ° C. for 30 minutes to obtain a free-standing polyaniline film having a thickness of 24 μm. The conductivity of this film is 1.3
S / cm.

When the ESR spectrum of this film was measured, a sharp signal having a narrow line width was obtained. The spin concentration was 1.2 × 10 ²⁰ spin / g. Example 11 In Example 10, dipentamethylene thiuram disulphide was used instead of tetramethylthiuram disulphide.
A homogeneous polyaniline solution was obtained without precipitation, in the same manner as in Example 10 except that 319 g was used.

Using this solution, a 26 μm-thick self-supporting polyaniline film was obtained in the same manner as in Example 10. The conductivity of this film was 0.38 S / cm. Comparative Example 2 In Example 1, when anhydrous ferric chloride as a normal oxidizing agent was used instead of tetramethylthiuram disulfide, reduced polyaniline was immediately oxidized to oxidized polyaniline at room temperature. . The solution containing polyaniline gradually solidified due to the coexistence of the protonic acid. Example 12 0.2 g of the imino-p-phenylene-type organic solvent-soluble polyaniline obtained in Reference Example 6 was added at room temperature to N-methyl-2.
-Dissolved in 9.8 g of pyrrolidone to prepare 10 g of a 2% by weight solution. This solution is designated as E.

Separately, p-toluenesulfonic acid monohydrate was added.
21 g was dissolved in 9.79 g of N-methyl-2-pyrrolidone to prepare 10 g of a 2.1% by weight solution. This is designated as solution F. In 10 g of this solution F, 0.044 g of tetramethylthiuram disulfide was dissolved. Then, this p-
Solution F containing toluenesulfonic acid and a thiuram compound dissolved therein was gradually added to the solution E at room temperature with stirring,
A homogeneous solution was obtained without forming a precipitate.

This solution was 10 cm × 10 cm, and had a thickness of 75 μm.
Was spin-coated on a polyethylene terephthalate film and dried by heating at 120 ° C. for 5 minutes to obtain a polyaniline film. The surface resistance of this film is 3.2 × 10
^{It was 5} Ω / □. When the cross section of this film was observed with a transmission electron microscope, the thickness was 0.08 μm. Example 13 A polyaniline film was obtained in the same manner as in Example 11, except that 0.0228 g of p-quinonedioxime was used in place of tetramethylthiuram disulfide. The surface resistance of this film is 2.5 × 10 ⁵ Ω
/ □. Example 14 A polyaniline film was obtained in the same manner as in Example 12, except that 0.103 g of cobalt stearate was dissolved before dissolving p-quinonedioxime. The surface resistance of this film is 1.1 × 10 ⁵ Ω / □
It was. Example 15 A polyaniline film was obtained in the same manner as in Example 11, except that 0.103 g of cobalt stearate was used instead of tetramethylthiuram disulphide. The surface resistance of this film is 8.5 × 10 ⁶ Ω /
□ Comparative Example 3 A polyaniline film was obtained in the same manner as in Example 12, except that tetramethylthiuram disulfide was not used. The surface resistance of this film was 4 × 10 ⁹ Ω / □.

[Brief description of the drawings]

FIG. 1 shows a laser Raman spectrum when quinone diimine / phenylenediamine type solvent-soluble polyaniline in an undoped state is excited with light having a wavelength of 457.9 nm.

FIG. 2 shows a conventional polyaniline of 45
Laser Raman spectrum when excited with light of 7.9 nm wavelength,

FIG. 3 is a laser Raman spectrum when the same quinone diimine / phenylenediamine type solvent-soluble polyaniline as in FIG. 1 is excited with light having various excitation wavelengths,

FIG. 4 is an electronic spectrum of a quinonediimine / phenylenediamine type solvent-soluble polyaniline solution in N-methyl-2-pyrrolidone.

FIG. 5 is a graph showing an example of the molecular weight distribution of quinone diimine / phenylenediamine type solvent-soluble polyaniline measured by GPC.

FIG. 6 is an FT-IR spectrum of a quinone diimine / phenylenediamine type solvent-soluble polyaniline in a dedoped state by a KBr tablet method,

FIG. 7 is an FT-IR spectrum of a solvent-insoluble film obtained by casting quinone diimine / phenylenediamine type solvent-soluble polyaniline by a KBr tablet method,

FIG. 8 shows the thermogravimetric analysis of the quinone diimine / phenylenediamine type solvent-soluble polyaniline film and the insolubilized film thereof,

FIG. 9 is a diagram showing a change in ESR spectrum when quinone diimine / phenylenediamine type solvent-soluble polyaniline is heated,

FIG. 10 is a reflection spectrum in the near-infrared region of a quinone diimine / phenylenediamine type solvent-soluble polyaniline film in a undoped state and a film doped with perchloric acid.

──────────────────────────────────────────────────続 き Continued on the front page (72) Minoru Ezoe, 1-2-1, Shimohozumi, Ibaraki-shi, Osaka Nitto Denko Corporation (56) References JP-A-2-240163 (JP, A) (58) ) Field surveyed (Int. Cl. ⁶ , DB name) C08G 73/00 C08L 79/00

Claims (8)

(57) [Claims] (1) (a) An organic polymer having an imino-p-phenylene structural unit represented by the following as a main repeating unit and being soluble in an organic solvent; (b) a protic acid or a protic acid derivative having a pKa value of 4.8 or less; and (c) ) Has no oxidizing power at normal temperature,
An organic polymer solution obtained by dissolving an oxidizing agent having an oxidizing power at a temperature of 60 ° C. or higher in an organic solvent. (2) (a) An organic polymer having an imino-p-phenylene structural unit represented by the following as a main repeating unit and being soluble in an organic solvent; (b) a protic acid or a protic acid derivative having a pKa value of 4.8 or less, and (d) An organic polymer solution obtained by dissolving an oxidation catalyst in an organic solvent. (3) (a) An organic polymer having an imino-p-phenylene structural unit represented by the following as a main repeating unit and soluble in an organic solvent, (b) a proton acid or a proton acid derivative having a pKa value of 4.8 or less, (c) Has no oxidizing power at normal temperature, 60
An oxidizing agent having an oxidizing power at a temperature of not less than ℃, and (d)
An organic polymer solution obtained by dissolving an oxidation catalyst in an organic solvent. 4. The organic compound according to claim 2, wherein the oxidation catalyst is at least one selected from the group consisting of cobalt, iron or manganese stearate, naphthenate and acetylacetonate. Polymer solution. 5. The method according to claim 1, wherein the oxidizing agent is (Wherein Ra, Rb, Rc and Rd each independently represent an alkyl group, and x represents an integer of 1 to 6.) 4. A thiuram-based compound represented by the formula: Organic polymer solution. 6. The method according to claim 1, wherein the oxidizing agent is (Wherein, Re and Rf each independently represent a hydrogen atom, an alkyl group or an oxyalkylene group.) 2. A sulfenamide compound represented by the formula:
Or the organic polymer solution according to 3. 7. The method according to claim 1, wherein the oxidizing agent is 4. The organic polymer solution according to claim 1, wherein the organic polymer solution is an oxime compound represented by the formula: wherein Rg and Rh each independently represent a hydroxyl group or a benzoyl group. 8. The organic polymer according to claim 1, wherein the intrinsic viscosity [η] measured in N-methyl-2-pyrrolidone at 30 ° C. is 0.40 dl / g or more. Organic polymer solution.